1. Field of the Invention
The invention relates to a support for disk-shaped articles, especially for silicon disks during the etching thereof, making use of the Bernoulli principle, with at least one preferably annular nozzle arranged in the peripheral zone of the support in the preferably circular surface of the support facing the article. This nozzle is fed with compressed gas for the formation of a gas cushion between the support and the disk-shaped article. Stops are located on the surface of the support facing the article in the peripheral zone of this support for the lateral retention of the disk-shaped article. These stops are constituted by cams arranged on shafts rotatably mounted in the support eccentrically to the axes of rotation of these shafts. The shafts carp/pinions meshing with a gear rim provided in the support to be rotatable about the central axis of the latter. The gear rim is coupled with the supporting shaft, at one end of which the support is provided. Gas flows to the nozzle through the hollow supporting shaft. For rotating the support, a rotary drive mechanism, preferably a gear wheel -toothed belt mechanism, engages the supporting shaft at a distance above its lower end. The support is provided with a brake.
2. Description of the Related Art
Such a support has been known from U.S. Pat. No. 4,903,717. In this conventional support, the drive mechanism for rotating the cams is partially accommodated in the space of the support through which the compressed gas flows to the nozzle. This arrangement has proven to be disadvantageous because abraded matter produced when the cams are rotated is blown by the compressed gas through the nozzle toward the outside and settles on the disk-shaped article retained on the support. Another drawback is that the gas flow through the support to the nozzle is impaired by the drive mechanism for rotation of the cams.